Earth’s skies have grown increasingly brighter over the years, as humans accelerate their love of electricity. Then came 2020, the year of lockdowns. One welcome side effect has been reduced light pollution.
A recent U.K. star count organized by a charity called CPRE found that light pollution continues to drop, with a 10% reduction since last year. Between February 6 and 14, 2021, CPRE collected nearly 8,000 star counts. If a person could only see 10 or fewer stars, that was considered severe light pollution. The group concluded that U.K. skies are the darkest they’ve been since 2013.
“Looking up at a starry night sky is a magical sight and one that we believe everyone should be able to experience, wherever they live,” said Crispin Truman, chief executive of CPRE. “And the great thing is, light pollution is one of the easiest kinds of pollution to reverse.”
Bright lights at night are more than just an annoyance. Many animals suffer when they get confused between day and night. “The introduction of artificial light probably represents the most drastic change human beings have made to their environment,” research scientist Christopher Kyba said of nocturnal animals. Cities are hundreds, if not thousands, of times brighter than they were 200 years ago. This messes up the cover that prey species rely upon, disrupts the nighttime croaking of frogs trying to attract a mate, confuses baby sea turtles who follow artificial lights away from the ocean and lures migratory birds off course.
So how do we reverse light pollution? The easiest way is to turn lights off when they’re not needed. Instead of leaving outdoor security lights on at night, install motion sensors so they only turn on when needed. Encourage your local government to use only covered streetlights with the bulbs pointing down. Colored lights, such as red, yellow and amber, cause less light pollution than white light. Consider lining your pathways with glow stones for nighttime lighting. Their ambient glow doesn’t contribute to light pollution.
Dan Monk, an astronomer in the U.K., said, “People often do get emotional when they sit under this amazing dark sky and they realize how small they are in the universe.” If we all do our part, we can share this experience.
Image via Felix Mittermeier